Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\\\\"(.*?)\\\\\""; final String string = "{\"unit\":{\"id\":1,\"val\":\"px\",\"name\":\"px\"},\"type\":{\"id\":3,\"val\":\"HORIZONTAL_BAR\",\"name\":\"Horizontal Bar\"},\"zoom\":{\"id\":2,\"val\":\"DEFAULT\",\"name\":\"Show\"},\"scale\":{\"id\":2,\"val\":\"TRUE\",\"name\":\"Show\"},\"fullscreen\":{\"id\":1,\"val\":\"FALSE\",\"name\":\"Hide\"},\"street\":{\"id\":2,\"val\":\"TRUE\",\"name\":\"Show\"},\"poi\":{\"id\":1,\"val\":\"FALSE\",\"name\":\"Disable\"},\"draggable\":{\"id\":2,\"val\":\"TRUE\",\"name\":\"Enable\"},\"doubleclick\":{\"id\":2,\"val\":\"TRUE\",\"name\":\"Enable\"},\"mouse\":{\"id\":2,\"val\":\"TRUE\",\"name\":\"Enable\"},\"gesture\":{\"id\":2,\"val\":\"auto\",\"name\":\"Auto\"},\"map\":{\"id\":1,\"val\":\"ROADMAP\",\"name\":\"Road Map\"},\"mapid\":\"mapkit-9479\",\"api\":\"\",\"lat\":\"51.343695608206275\",\"lng\":\"-2.4871419408111706\",\"zoomlvl\":13,\"width\":600,\"height\":400,\"position\":{},\"route\":{},\"infowindow\":{\"enable\":false,\"title\":false,\"tel\":false,\"email\":false,\"web\":false,\"desc\":false},\"visible\":1,\"lon\":\"-2.4871419408111706\",\"user_id\":4575,\"map_url\":\"26T9Te\",\"snazzy\":{\"id\":12,\"snazzy_id\":11,\"name\":\"Blue\",\"json\":\"[{\\\"featureType\\\":\\\"all\\\",\\\"stylers\\\":[{\\\"hue\\\":\\\"#0000b0\\\"},{\\\"invert_lightness\\\":\"true\"},{\\\"saturation\\\":-30}]}]\"}}"; final String subst = "\"$1\""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html